A transducer is a device that converts one type of energy to another. The conversion can be to/from electrical, electro-mechanical, electromagnetic, photonic, photovoltaic, or any other form of energy. While the term “transducer” commonly implies use as a sensor/detector, any device which converts energy can be considered a transducer. A transducer, or transducer kit (TK), is often categorized by application: sensor, actuator, or combination.
A transducer in the form of a sensor is used to detect a parameter in one form and report it in another form of energy (usually an electrical and/or digital signal). For example, a pressure sensor might detect pressure (a mechanical form of energy) and convert it to electricity for display at a remote gauge.
A transducer in the form of an actuator accepts energy and produces movement (action). The energy supplied to an actuator might be electrical or mechanical (pneumatic, hydraulic, etc.). An electric motor and a loudspeaker are both transducers, converting electrical energy into motion for different purposes.
Combination transducers have both functions—they both detect and create action. For example, a typical ultrasonic transducer switches back and forth many times a second between acting as an actuator to produce ultrasonic waves, and acting as a sensor to detect ultrasonic waves.
Modern TK devices are interfaced with a personal computer through the use of a cable connection, such as a Universal Serial Bus (USB), or the like. The interface allows the computer to record measurements as they are made if the transducer is functioning as a sensor, or send commands to the transducer, if the transducer is functioning as an actuator.
However, using an actual wire connection between a TK and a computer, such as a USB or the like, is limiting because the TK and device under test must be located at a distance in relation to the computer. The distance between the TK and device under test must be substantially equal to or less than the length of the wire because the wire must be connected to both the computer and the transducer. This limits the use of a TK when it is physically impossible to have the device under test in proximity to the computer such that the wire connection can be made between the TK and the computer.
Several attempts have been made to provide a wireless connection between a transducer or other diagnostic sensor, and a device such as a computer or protocol adapter. Many of these attempts have involved converting a first communications protocol in the form of an analog signal to a digital signal, then converting the digital signal to a wireless communications protocol, such as an RF or infrared signal, and transmitting the signal wirelessly from the transducer or other diagnostic sensor to the protocol adapter or computer, then performing another protocol conversion to convert the signal from a wireless signal back to a digital signal suitable for use with the communication protocol used by the protocol adapter or computer. However, this process involves several protocol conversions, such as analog-to-digital and digital-to-analog, and wireless to digital. Additionally, the upper frequency end of messages or sensor signals is restricted, and because there are at least two adapters for performing the analog-to-digital and digital-to-analog conversions, the device or system has an increased number of components.
Accordingly, there exists a need for a device such as a TK which is able to record desired measurements or parameters of a device under test, and communicate wirelessly with a computer, allowing the computer to record the measurements or parameters, without limiting the location of the computer or the device under test, while limiting the amount of conversions of the signal from the TK.